Make screenshot plugin optional

[ppitonak]

Is your feature request related to a problem? Please describe.
My team has a test suite that doesn't contain any web-based scenarios, only API. It doesn't make sense to have plugin screenshot installed and enabled.

Describe the solution you'd like
Screenshot plugin is not enabled by default or it's possible to disable it per-project.

Describe alternatives you've considered
At the moment, we are installing the plugin but ignore it.

Additional context
Discussed in #2069

[sriv]

This makes sense @ppitonak. In #2069 - I was referring to a config that would turn off reporting altogether. Is that what you seek here? Or is it the ability to turn of screenshot alone?

[ppitonak]

Turning off screenshot is enough for my use-case but I agree that disabling reporting makes sense, too.

[Flintols]

also would like the option of making the screenshot readable in report (we should be able to adjust size of screenshot in the report)